3 Description

F07HSF (ZPBTRS) is used to solve a complex Hermitian positive definite band system of linear equations AX=B, the routine must be preceded by a call to F07HRF (ZPBTRF) which computes the Cholesky factorization of A. The solution X is computed by forward and backward substitution.

If UPLO='U', A=UHU, where U is upper triangular; the solution X is computed by solving UHY=B and then UX=Y.

If UPLO='L', A=LLH, where L is lower triangular; the solution X is computed by solving LY=B and then LHX=Y.